Localized Energy Dissipation Structures For Vehicles

ABSTRACT

An impact protection structure for a vehicle impacting a blunt-object barrier includes a support structure of the vehicle, an energy absorbing rail coupled to the support structure, and a localized energy dissipation structure. The energy absorbing rail extends an energy absorbing rail length and includes a plurality of lumens. The localized energy dissipation structure extends a localized energy dissipation structure length less than the energy absorbing rail length.

TECHNICAL FIELD

The present specification generally relates to localized energydissipation structures for vehicles and, more specifically, to localizedenergy dissipation structures for vehicles that dissipate energyassociated with an impact with a blunt-object barrier at discretelocations along a portion of the vehicle.

BACKGROUND

Passenger vehicles must be capable of withstanding the high forcesexperienced during collisions. In the United States, vehicles mustcomply with the Federal Motor Vehicle Safety Standards (FMVSS) andInsurance Institute for Highway Safety protocols, which describe, amongother specifications, crashworthiness and vehicle integrity standards.

In addition to the standards applicable to conventional, gasoline ordiesel-fueled vehicles, in electric and hybrid-electric vehicles, it isimportant to protect the integrity of the battery packs that are used topower the vehicle. The energy that is required to be dissipated by animpact protection structure may vary depending on the location and theorientation of the impact protection structure. Accordingly, a needexists for localized energy dissipation structures for vehicles andvehicles incorporating the same.

SUMMARY

In one embodiment, an impact protection structure for a vehicleimpacting a blunt-object barrier includes a support structure of thevehicle, an energy absorbing rail coupled to the support structure, anda localized energy dissipation structure. The energy absorbing railextends an energy absorbing rail length and includes a plurality oflumens. The localized energy dissipation structure extends a localizedenergy dissipation structure length less than the energy absorbing raillength.

In another embodiment, an impact protection structure for a vehicleincludes a side sill of the vehicle extending a side sill distancebetween a front wheel well and a rear wheel well, and a plurality oflocalized energy dissipation structures coupled to the side sill, thelocalized energy dissipation structures each having a localized energydissipation structure length less than the side sill distance.

In yet another embodiment, an impact protection structure for a vehicleincludes a support structure for the vehicle, a mounting bracket coupledto the support structure, and a plurality of elongated frustums coupledto the mounting bracket. Each of the elongated frustums includes aplurality of lateral faces extending from the mounting bracket to adistal contact face, where the lateral face at the lowest verticalposition is angled upwards in a direction from the mounting bracket tothe distal contact face. When the elongated frustum is subject to animpact load, the elongated frustum deforms to absorb energy from theimpact load.

These and additional features provided by the embodiments describedherein will be more fully understood in view of the following detaileddescription, in conjunction with the drawings.

BRIEF DESCRIPTION OF THE DRAWINGS

The embodiments set forth in the drawings are illustrative and exemplaryin nature and not intended to limit the subject matter defined by theclaims. The following detailed description of the illustrativeembodiments can be understood when read in conjunction with thefollowing drawings, where like structure is indicated with likereference numerals and in which:

FIG. 1 schematically depicts a partial side view of a vehicle having animpact protection structure positioned along the side of the vehicleaccording to one or more embodiments shown or described herein;

FIG. 2 schematically depicts a perspective view of a support structureand impact protection structures for a vehicle according to one or moreembodiments shown or described herein;

FIG. 3 schematically depicts a perspective view of a localized energydissipation structure for an impact protection structure according toone or more embodiments shown or described herein;

FIG. 4 schematically depicts a front sectional view of an impactprotection structure for a vehicle including a localized energydissipation structure shown along line A-A of FIG. 1 according to one ormore embodiments shown or described herein;

FIG. 5 schematically depicts a front sectional view of the impactprotection structure including a localized energy dissipation structureof FIG. 4 along line A-A of FIG. 1 shown after impact with ablunt-object barrier;

FIG. 6 schematically depicts a front sectional view of an impactprotection structure for a vehicle including a localized energydissipation structure shown along line A-A of FIG. 1 according to one ormore embodiments shown or described herein;

FIG. 7 schematically depicts a perspective view of a battery supporttray and impact protection structures for a vehicle according to one ormore embodiments shown or described herein;

FIG. 8 schematically depicts a partial side view of a vehicle having animpact protection structure positioned along the side of the vehicleaccording to one or more embodiments shown or described herein;

FIG. 9 schematically depicts a front sectional view of an impactprotection structure for a vehicle including a localized energydissipation structure along line B-B of FIG. 7 according to one or moreembodiments shown or described herein;

FIG. 10 schematically depicts a perspective view of a battery supporttray for a vehicle according to one or more embodiments shown ordescribed herein;

FIG. 11 schematically depicts a perspective view of a localized energydissipation structure for a vehicle according to one or more embodimentsshown or described herein;

FIG. 12 schematically depicts a perspective view of a battery supporttray and impact protection structures for a vehicle according to one ormore embodiments shown or described herein;

FIG. 13 schematically depicts a front view of an impact protectionstructure for a vehicle according to one or more embodiments shown ordescribed herein;

FIG. 14 schematically depicts a top view of an impact protectionstructure for a vehicle according to one or more embodiments shown ordescribed herein;

FIG. 15 schematically depicts a top view of the impact protectionstructure for a vehicle of FIG. 14 undergoing an impact event with ablunt-object barrier;

FIG. 16 schematically depicts a top view of the impact protectionstructure for a vehicle of FIG. 14 undergoing an impact event with ablunt-object barrier;

FIG. 17 schematically depicts a top view of the impact protectionstructure for a vehicle of FIG. 14 undergoing an impact event with ablunt-object barrier; and

FIG. 18 hypothetically depicts a force-stroke plot diagrammaticallydepicting deformation of an impact protection structure undergoing animpact with a blunt-object barrier according to one or more embodimentsshown and described herein.

DETAILED DESCRIPTION

FIGS. 1 and 2 generally depict vehicles incorporating impact protectionstructures that deform when impacted by a blunt-object barrier and limitdamage to the vehicle from the blunt-object barrier. The impactprotection structures deform when impacted by the blunt-object barrier,such that the impact protection structures absorb energy associated withthe impact and prevent that energy from being transferred to the vehicleand/or the support structure of the vehicle. The impact protectionstructures include localized energy dissipation structures that extend adistance less than a distance the impact protection structures extendalong the side sills of the vehicle. The localized energy dissipationstructures allow placement of further impact protection structures inregions of low clearance and/or in discrete locations where additionalimpact protection is desired. The impact protection structures andvehicles incorporating the same will be described in more detail hereinwith specific reference to the appended drawings.

Referring now to FIG. 1, a partial side view of a vehicle 60 isdepicted. The vehicle 60 includes a side sill 62 that extends along oneside of the vehicle 60 from the front wheel 68 a to the rear wheel 68 ba side sill length 63. The vehicle 60 includes a corresponding side sill62 along the opposite side of the vehicle 60 (not shown). An impactprotection structure 100 is positioned along a side of the vehicle 60.The impact protection structure 100 is coupled to a support structure ofthe vehicle. As used herein, the phrase “support structure” may refer toa battery support tray (as described below), a vehicle frame or unibody64 of the vehicle 60.

Referring now to FIGS. 1 and 2, a battery support tray 90 of a vehicle60 is depicted. The battery support tray 90 includes a plurality ofcross-support members 96 that are coupled to a tray floor 94. Thecross-support members 96 may be coupled to end plates 92 positioned atthe ends of the cross-support members 96 for attachment to the impactprotection structures 100. The cross-support members 96 may beconstructed to satisfy the requirements of stiffness and strength toprovide support to the impact protection structure 100 during an impactevent, as described below. In one embodiment, the cross-support members96 include a plurality of components that are attached to each other.The cross-support members 96 may include hollow lumens arranged throughtheir thickness. The cross-support members 96 may be made from a varietyof materials including, without limitation, extruded aluminum alloychannels and steel channels.

In some embodiments, the impact protection structures 100 may beattached to both the vehicle frame or unibody 64 and the battery supporttray 90. In other embodiments, the impact protection structures 100 maybe secured directly to the battery support tray 90 without the impactprotection structures 100 being attached to the vehicle frame or unibody64.

While specific mention is made to the use of impact protectionstructures 100 with battery support trays 90 for electric orhybrid-electric vehicles, it should be understood that impact protectionstructures 100 according to the present disclosure may be used inconjunction with conventional, gasoline or diesel-fueled vehicles.

The impact protection structure 100 includes an energy absorbing rail108. In some embodiments, the energy absorbing rail 108 includes aninterior rail 110 coupled to the battery support tray 90 and an exteriorrail 120 coupled to the interior rail 110. In other embodiments, theenergy absorbing rail 108 is a single, integral rail. As depicted inFIG. 2, both the interior rail 110 and the exterior rail 120 includemulti-lumen structures. The lumens 124 of the exterior rail 120 areseparated by exterior rail septa 125, as will be described in greaterdetail below. The interior and exterior rail 110, 120 may be extrudedsuch that the wall thicknesses of the interior and exterior rails 110,120 are generally uniform along a length 111 of the energy absorbingrail 108.

As depicted in FIG. 1, the impact protection structure 100 is coupled tothe underside of the vehicle 60. A portion of the exterior rail 120 andthe localized energy dissipation structure 130 of the impact protectionstructure 100 may be visible along the side of the vehicle 60. Forexample, in the embodiment depicted in FIG. 1, a portion of the exteriorrail 120 is visible below the side sill 62 of the vehicle 60. However,in alternate embodiments, the impact protection structure 100 may becompletely visible or completely shielded from view by trim or bodycomponents of the vehicle 60.

It should be understood that the battery support tray 90 may be modularand interchangeable for use in a variety of vehicle platforms. Theinterchangeability of the battery support tray 90 across a variety ofvehicle platforms may allow the battery support tray 90 to be usedacross multiple vehicle lines, which may decrease costs associated withdevelopment and/or production of the vehicle 60. The impact protectionstructure 100, including the interior rail 110 and the exterior rail120, may be designed to suit particular vehicle layout requirements, forexample, by accommodating the packaging constraints of the particularvehicle and providing the desired side impact protection, whilecontinuing to use the interchangeable battery support tray 90.

In certain end-user applications, components of the vehicle 60 mayprevent installation of the impact protection structures 100 along anentire characteristic distance of the vehicle 60, for example along theentire side sill 62 of the vehicle 60. For example, suspensioncomponents (not shown) of the vehicle 60 that secure the wheels 68 a, 68b to the vehicle frame or unibody 64 may require clearance in locationsproximate to the impact protection structures 100 for installationand/or range of motion purposes. Accordingly, portions of the interiorand/or exterior rails 110, 120 of the impact protection structures 100may be removed from the interior and/or exterior rails 110, 120 to formrelief zones 128 in the impact protection structures 100. As depicted inFIGS. 1 and 2, the relief zones 128 are formed by removing a portion ofthe exterior rail 120 to expose a septum 125 of the exterior rail 120.The relief zones 128 extend into the exterior rail 120 of the energyabsorbing rail 108 and are positioned proximate to the wheels 68 a, 68 bof the vehicle 60.

The energy absorbing capacity of the energy absorbing rail 108 atpositions of the relief zones 128 (depicted in FIGS. 1 and 2 as beingpositioned at the furthest distance from the center of gravity 66 of thevehicle 60 in a forward direction 50 towards the front wheel 68 a) arereduced compared with the energy absorbing capacity of the energyabsorbing rail 108 at positions away from the relief zones 128. However,the relief zones 128 are positioned at an offset distance 140 in anoffset direction (i.e., in the forward direction 50) from the center ofgravity 66 of the vehicle 60. In an impact event where a blunt-objectbarrier contacts the vehicle 60 at a position away from the center ofgravity 66, the vehicle 60 will tend to rotate the vehicle around theblunt-object barrier. The rotation of the vehicle 60 around theblunt-object barrier reduces the energy that is transferred to theimpact protection structure 100 because the impact causes the force tobe applied in an oblique direction instead of normal to impactprotection structure 100. As such, energy dissipation requirements ofthe impact protection structure 100 are generally lower at locationsaway from the center of gravity 66 of the vehicle 60. Further, atlocations of the impact proximate to the relief zones 128, other vehiclestructures such as body panels, door panels, and portions of the vehicleframe or unibody 64 may dissipate energy associated with an impact witha blunt-object barrier. Thus, the required energy dissipation of theenergy absorbing rail 108 at positions proximate to the relief zones 128may be reduced.

As used herein, “blunt-object barrier” 70 (as depicted in FIG. 5) refersto a pole-like barrier used in testing according to FMVSS 201 and 214.Such a pole-like barrier simulates vehicle impact with telephone poles,trees, concrete posts, and the like. However, impact protectionstructures 100 according to the present disclosure may be utilized toresist impact by a variety of blunt-objects including real-worldimpacts.

Still referring to FIGS. 1 and 2, a localized energy dissipationstructure 130 a is positioned within the relief zones 128 of the energyabsorbing rail 108. As illustrated, the localized energy dissipationstructure 130 is positioned adjacent to an opening created in a lumen124 by the relief zone 128. By positioning the localized energydissipation structure 130 within the relief zone 128, additional sideimpact protection can be provided to the vehicle 60 at locationsproximate to the relief zones 128 without increasing the overall size ofthe impact protection structure 100. Such a localized energy dissipationstructure 130 may allow for installation of various vehicle componentsand provide access for later maintenance of vehicle components, forexample, maintenance of the battery packs 80 secured within the batterysupport tray 90 of the vehicle 60.

Referring now to FIG. 3, one embodiment of the localized energydissipation structure 130 is depicted. The localized energy dissipationstructure 130 includes an exterior profile 132 that generallycorresponds to the interior profile of one of the lumens 124 of theenergy absorbing rail 108. The exterior profile 132 of the localizedenergy dissipation structure 130 allows for a close fit between thelocalized energy dissipation structure 130 and the energy absorbing rail108. The localized energy dissipation structure 130 may be a multi-lumenstructure, for example, having a first and a second localized lumen 134a, 134 b that extend along a localized energy dissipation structurelength 138, which are separated by a septum 135. By incorporating afirst and second localized lumen 134 a, 134 b, the localized energydissipation structure 130 may have an increased resistance to bucklingwhen a load is applied to the localized energy dissipation structure 130than a localized energy dissipation structure that does not incorporatea first and second localized lumen 134 a, 134 b.

The impact protection structure 100, including the energy absorbing rail108 and the localized energy dissipation structure 130 may be made froma variety of materials including, for example, alloys of aluminum orsteel. Some components of the impact protection structure 100 may beformed in an extrusion process such that the components have generallyuniform wall thicknesses along their lengths. Alternatively, somecomponents of the impact protection structure 100 may be fabricated asseparate components that are secured to one another with mechanicalfasteners (not shown). The mechanical fasteners may be, but are notlimited to, pop rivets, solid core rivets, or self piercing rivets madefrom a variety of materials including, but not limited to, alloys ofaluminum or steel. The mechanical fasteners may also be bolts and nutsor screws. The components of the impact protection structure 100 mayalso be secured to one another by a structural adhesive, for example anepoxy or an acrylic resin. Alternatively, or in addition, components ofthe impact protection structure 100 may be fabricated through a joiningprocess, for example welding, including resistance spot welding,friction stir welding, gas tungsten arc welding, gas metal arc welding,or brazing, such that the components of the impact protection structure100 are weldments.

Referring again to FIG. 1, another embodiment of the localized energydissipation structure 130 b is depicted, where the localized energydissipation structure 130 is located internally to the energy absorbingrail 108. The localized energy dissipation structure 130 b includes alocalized energy dissipation structure length 138 that is less than thelength 111 of the interior and/or exterior rails 110, 120 of the energyabsorbing rail 108. The localized energy dissipation structure 130 ispositioned along the energy absorbing rail 108 at a location whereadditional impact protection is desired. The localized energydissipation structure 130 b is coupled to the energy absorbing rail 108at a plurality of securement positions 139 along the localized energydissipation structure length 138. The plurality of securement positions139 may be spaced apart from one another at interstitial positionsbetween the securement positions 139.

Referring to FIG. 4, an embodiment of the localized energy dissipationstructure 130 positioned internally to an enclosed lumen 124 a of theenergy absorbing rail 108 is depicted. In this embodiment, the energyabsorbing rail 108 includes an interior rail 110 coupled to both the endplates 92 and the tray floor 94 of the battery support tray 90. Theinterior rail 110 is a multi-lumen structure having a first and secondinterior lumen 112 a, 112 b. The energy absorbing rail 108 also includesan exterior rail 120 coupled to the interior rail 110. In the depictedembodiment, the exterior rail 120 includes a first, second, third, andfourth exterior lumen 124 a, 124 b, 124 c, 124 d, each separated fromone another by an exterior rail septum 125. The localized energydissipation structure 130 is positioned within the first exterior lumen124 a at a pre-determined position along the length of the exterior rail120.

The localized energy dissipation structure 130 is coupled to theexterior rail 120 of the energy absorbing rail 108 at a plurality ofsecurement positions 139. In some embodiments, the localized energydissipation structure 130 and the energy absorbing rail 108 are securedto one another with mechanical fasteners. The mechanical fasteners maybe, but are not limited to, pop rivets, solid core rivets, or selfpiercing rivets made from a variety of materials including, but notlimited to, alloys of aluminum or steel. The mechanical fasteners mayalso be bolts and nuts or screws. The localized energy dissipationstructure 130 may also be secured to the energy absorbing rail 108 by astructural adhesive, for example an epoxy or an acrylic resin.Alternatively, or in addition, the localized energy dissipationstructure 130 may be secured to the energy absorbing rail 108 through ajoining process, for example welding, including resistance spot welding,friction stir welding, gas tungsten arc welding, gas metal arc welding,or brazing.

The interior rail 110 and the exterior rail 120 including the localizedenergy dissipation structure 130 each have an associated interiorbuckling load limit or exterior buckling load limit. The interior orexterior buckling load limit, as used herein, refers to the maximum loadthat can be applied to the interior rail 110 or the exterior rail 120before one of the lumens loses stability and collapses in an inboarddirection. The buckling load limit of any of the interior lumens 112 a,112 b or the exterior lumens 124 a, 124 b, 124 c, 124 d may be simulatedcomputationally, for example, using a non-linear finite element analysisprogram. The buckling load limit of the lumens may be approximated bycalculating the bending strength of each of the lumens when a force isapplied to the exterior rail 120 in an inboard direction. The bucklingload limit of any of the lumens, and therefore the interior rail 110 andexterior rail 120, may be affected by the shape and thickness of thewalls surrounding the lumens.

Referring now to FIG. 5, the energy absorbing rail 108 of FIG. 4 isdepicted undergoing an impact event with a blunt-object barrier 70. Asdepicted in FIG. 5, as the exterior rail 120 contacts the blunt-objectbarrier 70, the first exterior lumen 124 a buckles as the buckling loadlimit of the first exterior lumen 124 a is exceeded. In addition,because the localized energy dissipation structure 130 is positionedwithin the first exterior lumen 124 a of the exterior rail 120, as thefirst exterior lumen 124 a deforms, the localized energy dissipationstructure 130 deforms. The buckling of the localized energy dissipationstructure 130 increases the energy dissipated at the contact zone alongthe energy absorbing rail 108, thereby reducing the energy caused by theimpact event between the energy absorbing rail 108 and the blunt-objectbarrier 70. The increase in energy dissipation by the localized energydissipation structure 130 may decrease the energy due to the impactevent that is transferred towards the battery support tray 90, therebyreducing the likelihood of damage to the battery packs (not shown).

In the embodiment depicted in FIGS. 4 and 5, the buckling load limit ofthe exterior rail 120 is less than the buckling load limit of theinterior rail 110. As such, the exterior rail 120, including thelocalized energy dissipation structure 130, buckles before the interiorrail 110. By preferentially buckling the exterior rail 120 before theinterior rail 110, the deformation of the energy absorbing rail 108 maybe controlled such that the deformed shape of the energy absorbing rail108 does not induce an unsustainable moment load into the end plates 92or tray floor 94 of the battery support tray 90.

In the embodiment depicted in FIGS. 4 and 5, the localized energydissipation structure 130 increases the energy dissipation of the impactprotection structure 100 at a discrete location along the length 111 ofthe interior and exterior rails 110, 120. The localized energydissipation structure 130 may provide a comparable energy dissipation toan exterior rail 120 having an increased wall thickness along the entirelength 111 of the exterior rail 120, but without incurring the increasein weight associated with an increase in wall thickness along the entirelength 111. Thus, the localized energy dissipation structure 130 maydissipate energy more efficiently in regard to weight than an increasein wall thickness along the entire length 111 of the exterior rail 120.

Referring now to FIG. 6, another embodiment of the impact protectionstructure 100 is depicted. In this embodiment, portions of the exteriorrail 120 have been removed, as described above, exposing the exteriorrail septum 125 separating the second exterior lumen 124 b from thethird exterior lumen 124 c, thereby forming a relief zone 128 in theexterior rail 120. The localized energy dissipation structure 130 is amulti-lumen structure having a first and second localized lumens 134 a,134 b that are separated from one another by a septum 135. The localizedenergy dissipation structure 130 is positioned proximate to the reliefzone 128 within the third exterior lumen 124 c, which remains enclosed.The localized energy dissipation structure 130 extends along theexterior rail 120 a partial distance less than the length 111 of theexterior rail 120. The localized energy dissipation structure 130depicted in FIG. 6 provides additional strength to the exterior rail 120that increases the energy dissipation capability of the exterior rail120. Further, by positioning the localized energy dissipation structure130 within the third exterior lumen 124 c, the impact protectionstructure 100 exhibits an enhanced energy dissipation capability withoutincreasing the size of the exterior rail 120.

Referring now to FIGS. 7-9, another embodiment of the impact protectionstructure 100 including a plurality of localized energy dissipationstructures 230 is depicted. In this embodiment, the localized energydissipation structures 230 are coupled to the battery support tray 90 ofthe vehicle. Each of the localized energy dissipation structures 230 hasa localized energy dissipation structure length 238 that is less thanthe side sill length 63 extending from the front wheel well 69 a to therear wheel well 69 b of the vehicle 60, as depicted in FIG. 1. Thelocalized energy dissipation structures 230 are positioned along thebattery support tray 90 such that the plurality of localized energydissipation structures 230 provides impact protection to the batterysupport tray 90, and therefore the vehicle 60, along the entire sidesill length 63.

In the embodiment depicted in FIGS. 7-9, adjacent localized energydissipation structures 230 are overlapped with one another along thelength 138 of the localized energy dissipation structures 230.Accordingly, the exterior contour 232 of the localized energydissipation structures 230 may be shaped such that the top and thebottom of the localized energy dissipation structures “nest” with oneanother, as depicted in FIG. 9. As depicted in FIG. 8, the localizedenergy dissipation structures 230 may be biased relative to the batterysupport tray 90 such that a rearward portion 236 of a first localizedenergy dissipation structure 230 is positioned a vertical distance belowa forward portion 237 of a second localized energy dissipation structure230, where the first localized energy dissipation structure 230 ispositioned in a forward direction 50 of the second localized energydissipation structure 230. Such positioning of the localized energydissipation structures 230 may create an “offset nesting” arrangementthat increases the protection to an impact event with a blunt-objectbarrier 70 by increasing the available localized energy dissipationstructures 230 to absorb the impact. The offset nesting arrangement mayalso be helpful in shedding debris such as water, snow, and road grimefrom the impact protection structure 100. The localized energydissipation structures 230 may include weep holes to shed debris thatcollects inside the localized energy dissipation structures 230. In someembodiments, the overlap distance 242 of adjacent localized energydissipation structures 230 may be from about 20% to about 70% of thelength 238 of the localized energy dissipation structure. In aparticular embodiment, the overlap distance 242 of adjacent energydissipation structures 230 may be about 50% of the length 238 of thelocalized energy dissipation structure.

While the localized energy dissipation structures 230 depicted in FIG. 8are depicted to contact one another, it should be understood that thelocalized energy dissipation structures 230 may be spaced apart from oneanother to provide clearance to shed debris such as water, snow, roadgrime, and the like.

Referring now to FIG. 9, the localized energy dissipation structures 230may be a multi-lumen structure that includes a first and a second lumen234 a, 234 b. The first and second lumens 234 a, 234 b may be positionedwithin the localized energy dissipation structures 230 to provide apre-determined buckling load limit, based on the end-user application.

When a vehicle 60 having the localized energy dissipation structure 230is subject to an impact load from a blunt-object barrier, the localizedenergy dissipation structures 230 proximate to the blunt-object barriercontact the blunt-object barrier and being to deform. As the localizedenergy dissipation structures 230 elastically and/or plastically deform,the load applied to the localized energy dissipation structures 230exceeds the buckling load limit of the localized energy dissipationstructures 230, causing the localized energy dissipation structures 230to buckle due to the compressive stresses applied by the blunt-objectbarrier. Because the localized energy dissipation structures 230 arecoupled to the battery support tray 90 independently of one another, oneof the localized energy dissipation structures 230 may buckle, while anadjacent localized energy dissipation structure 230 does not.

Referring now to FIGS. 10 and 11, components of another embodiment ofthe battery support tray 90 and localized energy dissipation structures430 are depicted. Referring now to FIG. 10, the end plates 92 of thebattery support tray 90 include locating slots 394. The locating slots394 extend a partial distance along the side of the battery support tray90. Referring now to FIG. 11, each of the plurality of localized energydissipation structures 430 include a support tab 440 that extends awayfrom the plurality of localized lumens 434 a, 434 b, 434 c. The exteriorcontour 432 of the localized energy dissipation structures 430 is shapedto allow the localized energy dissipation structures 430 to “nest” withone another. When the localized energy dissipation structures 430 areinstalled in position on the battery support tray 90, the support tabs440 of the localized energy dissipation structures 430 are inserted intothe locating slots 394 of the end plates 92. By positioning the supporttabs 440 in the locating slots 394, the position and orientation of theplurality of localized energy dissipation structures 430 can bemaintained relative to the battery support tray 90 and to each other.

Still referring to FIG. 11, the localized energy dissipation structures430 may include interlocking tabs 442 extending from one of the top orthe bottom surface of the localized energy dissipation structure 430(depicted in FIG. 11 as extending from the top surface of the localizedenergy dissipation structure 430), and interlocking slots 444 thatextend along one of the bottom surface or the top surface of thelocalized energy dissipation structure 430 (depicted in FIG. 11 asextending from the bottom surface of the localized energy dissipationstructure 430). When the localized energy dissipation structures 430 areassembled in position on the battery support tray 90, the interlockingtabs 442 are positioned within the interlocking slots 444 such thatadjacent localized energy dissipation structures 430 are interlockedwith one another. Interlocking of adjacent localized energy dissipationstructures 430 may assist with dissipating energy associated with impactwith a blunt-object barrier. For example, when one of the localizedenergy dissipation structures 430 is impacted by a blunt-object barrier,the interlocking tabs 442 and the interlocking slots 444 may transferenergy from the localized energy dissipation structure 430 absorbing themajority of the energy from the impact to adjacent localized energydissipation structures 430.

Referring now to FIGS. 12-17, another embodiment of the impactprotection structure 300 for a vehicle is depicted. In this embodiment,the impact protection structure 300 includes a plurality of elongatedfrustums 310 coupled to the battery support tray 90 of the vehicle. Asdepicted in FIG. 12, the impact protection structures 300 are coupled tothe battery support tray 90 such that the elongated frustums 310 extendin the forward direction 50 of the vehicle. However, it should beunderstood that the impact protection structures 300 may be positionedsuch that the elongated frustums 310 extend in a rearward direction 52as well as in one of the lateral directions 56 of the vehicle.

Referring now to FIGS. 13 and 14, the elongated frustums 310 of theimpact protection structure 300 have a truncated-pyramid shape thatincludes a plurality of lateral faces 312 that extend outwards to adistal contact face 318. While the elongated frustums 310 depictedinclude four lateral faces 312, it should be understood that theelongated frustums 310 may include any of a number of lateral faces 312geometrically arranged, including an elongated frustum 310 having acone-like shape and, therefore, a single lateral face 312. The lateralfaces 312 extend away from the distal contact face 318 to mountingflanges 314. The mounting flanges 314 of the elongated frustum 310 arecoupled to a mounting bracket 322. The mounting flanges 314 may includea plurality of positioning datums 316 that assist with alignment of theelongated frustum 310 to the mounting bracket 322.

The impact protection structure 300 may also include a plurality of tiestraps 320 that are coupled to adjacent elongated frustums 310. The tiestraps 320 distribute load associated with an impact event with ablunt-object barrier 70 (not shown) away from the point of impact withthe distal contact face 318 to adjacent elongated frustums 310, therebydistributing the load and stabilizing the elongated frustums 310 andenhancing performance of the impact protection structure 300. The tiestraps 320 may extend along a majority of the lateral faces 312 of theelongated frustums 310. The tie straps 320 may be coupled to theelongated frustums 310 at a plurality of attachment points 323. The tietraps 320 may be coupled to the elongated frustums 310 at the attachmentpoints 323 by mechanical fasteners, structural adhesive, structural spotwelds, or a combination thereof.

In the embodiment depicted in FIGS. 12-14, the lateral face 312 of theelongated frustum 310 that is at the lowest vertical position is angledupwards from the mounting bracket 322 to the distal contact face 318.The angled orientation of the lowest vertically positioned lateral face312 may assist with shedding debris such as water, snow, road grime, andthe like, from the impact protection structure 300.

The elongated frustum 310 may be fabricated using a variety oftechniques including deep-draw stamping, hydroforming, and/or sheetmetal bending and welding, such that the elongated frustums 310 includeweldments. In some embodiments, the interior volume of the elongatedfrustums 310 defined by the lateral faces 312, the distal contact face318, and the mounting flanges 314 may be hollow. In other embodiments,the interior volume of the elongated frustums 310 may be filled with anenergy absorbing material.

Referring now to FIGS. 15-17, an impact event between an impactprotection structure 300 having a plurality of elongated frustums 310and a blunt-object barrier 70 is depicted. When a vehicle having theimpact protection structure 300 that includes a plurality of elongatedfrustums 310 is subject to an impact load from a blunt-object barrier70, the elongated frustums 310 proximate to the blunt-object barrier 70contact the blunt-object barrier 70 and being to deform. As theelongated frustums 310 elastically and/or plastically deform, the loadapplied to the elongated frustums 310 exceeds the buckling load limit ofthe elongated frustums 310, causing the elongated frustums 310 to buckleinwards towards the battery support tray 90 due to the compressivestresses applied by the blunt-object barrier 70. Depending on thelocation of the blunt-object barrier 70 relative to the elongatedfrustums 310, a load that is non-orthogonal to the distal contact face318 may tend to bend the elongated frustum 310, causing it to collapsein a direction corresponding to the direction of the load. As theelongated frustum 310 continues to buckle, the tie straps 320 maydistribute the load from the elongated frustum 310 contacting theblunt-object barrier 70 to elongated frustums 310 that are spaced apartfrom the blunt-object barrier 70. The tie straps 320 stabilize each ofthe elongated frustums 310 by distributing a portion of the loadassociated with the impact with the blunt-object barrier 70 to otherelongated frustums 310 in the impact protection structure 300.

Referring now to FIG. 15, the impact protection structure 300 includesthree elongated frustums 310 that are coupled to one another by tiestraps 320 at two positions along the top and bottom lateral faces 312.The tie straps 320 segregate the elongated frustums 310 into a pluralityof discrete deformation zones. A first deformation zone 330 ispositioned between the contact faces 318 of the elongated frustums 310and the outer-most tie strap 320. A second deformation zone 332 ispositioned between the outer-most tie strap 320 and the inner-most tiestrap 320. The third deformation zone 334 is positioned between theinner-most tie strap 320 and the mounting bracket 322 of the impactprotection structure 300. Referring to FIG. 15, when the elongatedfrustum 310 positioned in the center of the impact protection structure300 is contacted by a blunt object barrier 70, the elongated frustum 310contacting the blunt-object barrier 70 begins to deform in the firstdeformation zone 330.

Referring now to FIG. 16, as the blunt-object barrier 70 continues totravel towards the mounting bracket 322, the elongated frustum 310contacting the blunt-object barrier 70 continues to collapse and deform.As the elongated frustum 310 contacting the blunt-object barrier 70collapses in the first and second deformation zones 330, 332, theouter-most tie strap 320 applies a force to the non-contacting elongatedfrustums 310, causing the non-contacting elongated frustums 310 todeform. The tie strap 320 transfers energy caused by the impact betweenthe blunt-object barrier 70 and the contacting elongated frustum 310 tothe non-contacting elongated frustums 310, such that the non-contactingelongated frustums 310 dissipate energy associated with the impact. Thedeformation of the non-contacting elongated frustums 310 may bepositioned in the same deformation zone as that of the contactingelongated frustum 310. Thus, deformation of the contacting elongatedfrustum 310 in the first and second deformation zones 330, 332 may causedeformation of the non-contacting elongated frustums 310 in the firstand second deformation zone 332. Further, the tie strap 320 may providestructural reinforcement to local regions of the elongated frustums 310.The deformation of the elongated frustums 310 is limited to occur in thefirst and second deformation zones 330, 332, while local regions of theelongated frustums 310 supported by the tie straps 320 remainundeformed.

Referring now to FIG. 17, the contacting and non-contacting elongatedfrustums 310 continue to deform as the elongated frustums 310 dissipateenergy associated with the impact with the blunt-object barrier 70. Asdepicted in FIG. 17, the contacting frustum 310 deforms in the first,second, and third deformation zones 330, 332, 334 as the blunt-objectbarrier 70 approaches the mounting bracket 322. The outer-most andinner-most tie straps 320 apply loads to the non-contacting elongatedfrustums 310 as to dissipate energy associated with the impact. Further,as is depicted in FIG. 17, the deformation of the non-contactingelongated frustums 310 may be positioned in the same deformation zone asthat of the contacting elongated frustum 310. Thus, deformation of thecontacting elongated frustum 310 in the first, second, and thirddeformation zones 330, 332, 334 may cause deformation of thenon-contacting elongated frustums 310 in the first, second, and thirddeformation zones 330, 332, 334.

Referring now to FIG. 18, a hypothetical force-stroke plotdiagrammatically depicts deformation of the impact protection structure300 undergoing an impact with a blunt-object barrier. The individualcurves of the force-stroke plot represent the energy dissipation of thefirst, second, and third deformation zones 330, 332, 334 as the impactprotection structure 300 undergoes the impact event. Because of thetaper of the elongated frustums 310 from the distal contact face 318 tothe mounting bracket 322, the first, second, and third deformation zones330, 332, 334 have progressively increasing energy dissipationcapability, which is reflected in the ability of the elongated frustums310 to resist progressively greater deformation force as the first,second, and third deformation zones 330, 332, 334 buckle. Without beingbound by theory, the even taper of the elongated frustums 310 provideforce-stroke curves having approximately the same shape for the first,second, and third deformation zones 330, 332, 334, or are “symmetrical.”The symmetric force-stroke curves reflect that maximum force F_(MAX)dissipated by the impact protection structure 300 is progressive anddoes not containing sharp changes in slope, representative of suddenimpact loads being transferred to the vehicle. The hypotheticalforce-stroke plot depicting the response of the impact protectionstructure 300 with a blunt-object barrier (i.e., increase in force witheach successive buckle and symmetry of deformation zones 330, 332, 334)reflects computational results shown by nonlinear finite elementanalysis of the described shape.

It should now be understood that impact protection structures mayinclude localized energy dissipation structures that may be used inconjunction with other energy absorbing structures as to provide a localincrease in energy dissipation capability of the energy absorbingstructures. Impact protection structures that incorporate localizedenergy dissipation structures use material more efficiently, such that aweight penalty associated with increase energy dissipation is managed.Impact protection structures including localized energy dissipationstructures according to the present disclosure may be positioned at avariety of orientations on the vehicle to provide increased protectionfrom impact with blunt-object barriers in a variety of vehicleorientations.

It is noted that the terms “substantially” and “about” may be utilizedherein to represent the inherent degree of uncertainty that may beattributed to any quantitative comparison, value, measurement, or otherrepresentation. These terms are also utilized herein to represent thedegree by which a quantitative representation may vary from a statedreference without resulting in a change in the basic function of thesubject matter at issue.

While particular embodiments have been illustrated and described herein,it should be understood that various other changes and modifications maybe made without departing from the spirit and scope of the claimedsubject matter. Moreover, although various aspects of the claimedsubject matter have been described herein, such aspects need not beutilized in combination. It is therefore intended that the appendedclaims cover all such changes and modifications that are within thescope of the claimed subject matter.

1. An impact protection structure for a vehicle impacting a blunt-objectbarrier, the impact protection structure comprising: a support structureof the vehicle; an energy absorbing rail coupled to the supportstructure, the energy absorbing rail extending an energy absorbing raillength and comprising a plurality of lumens and a relief zone thatexposes a septum positioned between two adjacent lumens along a portionof a length of the energy absorbing rail; and a localized energydissipation structure coupled to the energy absorbing rail, thelocalized energy dissipation structure extending a localized energydissipation structure length less than the energy absorbing rail length,wherein the localized energy dissipation structure is positionedadjacent to the relief zone such that the localized energy dissipationstructure deforms when the localized energy dissipation structure isimpacted by the blunt-object barrier.
 2. The impact protection structureof claim 1, wherein the localized energy dissipation structure ispositioned inside one of the lumens of the energy absorbing rail suchthat the localized energy dissipation structure deforms with the energyabsorbing rail when the energy absorbing rail is impacted by theblunt-object barrier.
 3. The impact protection structure of claim 1,wherein the energy absorbing rail comprises: an interior rail coupled tothe support structure, the interior rail extending an interior raillength; and an exterior rail coupled to the interior rail, the exteriorrail comprising a plurality of interior lumens.
 4. The impact protectionstructure of claim 3, wherein the interior rail comprises apredetermined interior buckling load limit and the exterior rail and thelocalized energy dissipation structure have a predetermined exteriorbuckling load limit, wherein the exterior buckling load limit is lessthan the interior buckling load limit. 5-6. (canceled)
 7. The impactprotection structure of claim 1, wherein the localized energydissipation structure comprises a plurality of energy dissipation lumensextending along the localized distance of the localized energydissipation structure.
 8. The impact protection structure of claim 1,wherein the localized energy dissipation structure is coupled to theenergy absorbing rail at a plurality of securement positions along thelocalized distance.
 9. The impact protection structure of claim 8,wherein the localized energy dissipation structure is detached from theenergy absorbing rail at a plurality interstitial positions spacedbetween the plurality of securement positions. 10-20. (canceled)
 21. Animpact protection structure for a vehicle impacting a blunt-objectbarrier, the impact protection structure comprising: a support structureof the vehicle; an energy absorbing rail coupled to the supportstructure, the energy absorbing rail extending an energy absorbing raillength and comprising a plurality of lumens and a relief zone thatexposes a septum positioned between two adjacent lumens along a portionof a length of the energy absorbing rail; and a localized energydissipation structure coupled to the energy absorbing rail, thelocalized energy dissipation structure extending a localized energydissipation structure length less than the energy absorbing rail length,wherein the localized energy dissipation structure is positionedadjacent to the relief zone and is inserted into a lumen in the reliefzone that is enclosed such that the localized energy dissipationstructure deforms when the localized energy dissipation structure isimpacted by the blunt-object barrier.
 22. The impact protectionstructure of claim 21, wherein the localized energy dissipationstructure is positioned inside one of the lumens of the energy absorbingrail such that the localized energy dissipation structure deforms withthe energy absorbing rail when the energy absorbing rail is impacted bythe blunt-object barrier.
 23. The impact protection structure of claim21, wherein the energy absorbing rail comprises: an interior railcoupled to the support structure, the interior rail extending aninterior rail length; and an exterior rail coupled to the interior rail,the exterior rail comprising a plurality of interior lumens.
 24. Theimpact protection structure of claim 23, wherein the interior railcomprises a predetermined interior buckling load limit and the exteriorrail and the localized energy dissipation structure have a predeterminedexterior buckling load limit, wherein the exterior buckling load limitis less than the interior buckling load limit.
 25. The impact protectionstructure of claim 21, wherein the localized energy dissipationstructure comprises a plurality of energy dissipation lumens extendingalong the localized distance of the localized energy dissipationstructure.
 26. The impact protection structure of claim 21, wherein thelocalized energy dissipation structure is coupled to the energyabsorbing rail at a plurality of securement positions along thelocalized distance.
 27. The impact protection structure of claim 26,wherein the localized energy dissipation structure is detached from theenergy absorbing rail at a plurality interstitial positions spacedbetween the plurality of securement positions.